Type-writing machine.



J. G, MULAUGHLIN.

TYPE WRITING MACHINE. APPLIOATIO'N IILED M-ARUZB, 1910.

994,327, Patented June 6,1911.

UNITED STATES PATENT OFFICE.

JOHN G. MOLAUGHLIN, F JERSEY CITY, NEW JERSEY, ASS-IGNOR TO UNDERWOOD TYPEWRITER COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

TYPE-WRITING MACHINE.

Specification of Letters Patent.

' Patented June 6, 1911.

Application filed March 23, 1910. Serial No. 551,059.

To all whom it may concern:

- LIN, a citizen of the United States, residing in Jersey City, in the county of Hudson and State of New Jersey, have invented: certain new and useful Improvements in Type- Writing Machines, of which the following is a specification. r

This invention relates to the keys of typewriting machines, and particularly to the denomination keys of tabulating mechanisms.

The invention is pertinent to that class of machines in which one key is employed for different purposes, as in case of a tabulating mechanism, where it is sometimes desired to use the same stop for different denominations, and therefore to make a corresponding change in the key.

The object of the invention is to provide an improved, simplified and efficient means to effect changes in the keys for such purposes, and one which is easily operated, not liable to he accidentally displaced, and readily applicable to existing machines.

I provide the usual key lever with at least two separate character-bearing disks mounted on the opposite ends of a cross arm or head. The head has a sleeve or stem which fits upon a bearing formed on the forward end of the key lever, about which it turns to display one or theother of said characterbearing disks. The head is shiftable longitudinally of the bearing to engage and releaseitself from a detent which operates to lock the head in adjusted position against accidental displacement.

In the accompanying drawings, Figure 1 is a perspective view of a key lever provided with my invention, parts being broken away to better disclose the construction. Fig. 2 is a similar view showing the mechanism disassembled. Fig. 3 is a diagrammatic plan view, showing in the upper row a set of denomination keys, of which the first four are of ordinary construction and the last six are constructed in accordance with the invention. The second row shows the last six keys reversed to expose the characters on the oppositely located disks, so that the keys may now be used for difi'erent denominations. Fig. 1 is a side view of my invention, partly in section,

the key in released position. Fig. 6 is a diagrammatic side view showing the key lever and denomination stop.

The key is illustrated as mounted upon a lever 1, pivoted at 2. Said lever is connected to a rod 3 having at its upper end a denomination stop t,to cooperate with a column stop 5, carried upon a rack or bar 6 mounted upon the usual carriage (not shown). The key comprises a cross arm 7, to the opposite ends of which are rigidly secured the key disks 8, 8", bearing different characters. For instance, one key disk 8 bears a comma, the opposite key disk 8 bearing the characters 1 T, meaning one thousand. The key disks are formed in the usual manner and need no further description.

To reverse the key disks to change from one set of denominations to the other, a hollow stem or sleeve 9 is connected at right angles to the cross arm 7 andfitted to turn on a bearing 10 in which the forward end of the key lever 1 terminates. A screw 11 passes loosely through the cross-arm and stem into the end of the bearing to connect the key and key lever.

To look the reversible key against accidentally turning on the key lever, the latter is provided with one or more detents or proj ections 12, fitting into recesses or notches 13, in the outer end of the stem or sleeve. The recesses are held in engagement with the projections by a compression spring let encircling the screw between its head 16 and a partition 15 in the stem. By means of the screw, the spring is placed or held under tension to force the outer end of the sleeve against the projections, which when seated in the recesses resist turning of the key.

It will thus be seen that the denomination of the key can be readily changed by simply rotating the head carrying the opposed key disks. The head may be either pulled outward to release the stem or sleeve from the detents or projections 12 before rotation, or if desired, it may be rotated forcibly, until the recesses are once more brought into register with the detents, whereupon the spring snaps the recesses over the detents to hold the key.

Having thus described my invention, I claim:

1. A key comprising a cross-arm having character disks located at the opposite ends thereof, a key lever on which the key is rotatably mounted, and a detent mechanism effective to prevent accidental rotation of the key.

2. A key comprising a cross-arm bearing character disks at its opposite ends, a key lever on which the key is rotatably mounted, a detent on the lever engaged by recesses on the key, and a tension device to normally maintain the detent and recesses in engagement.

3. A key comprising a cross-arm bearing character disks at its opposite ends, a sleeve projecting from the cross-arm, a key lever terminating at its forward end in a bearing on which the sleeve is rotatably mounted, and a detent mechanism efl'ective to prevent accidental rotation of the key.

4. In a tabulating mechanism, the combination with a key lever, of a reversible key including a cross-arm having character disks at its opposite ends, a sleeve projecting from the cross-arm and fitted to turn upon a bearing on the key-lever, a fastening device connecting the key and key lever, and a detent mechanism effective to prevent accidental rotation of the key.

5. In a tabulating mechanism, the combination with a key lever, of a reversible key including a cross-arm having character disks at its opposite ends, a sleeve projecting from the cross-arm and fitted to turn upon a bearing on the key lever, a fastening de vice connecting the key and key lever, a detent on the key lever normally seated in a recess in the sleeve to prevent accidental rotation, and a spring to maintain the detent and recess in engagement.

6. A reversible character key comprising a rotatable cross-arm having character disks atits opposite ends, and a detent mechanism to hold the key in adjusted position.

7. In a tabulating mechanism, the combination with a key lever, of a reversible key including a cross-arm having character disks at its opposite ends, a sleeve projecting from the cross-arm and fitted to turn upon a bearing on the key lever, a screw passing loosely through the cross-arm and sleeve into the end of the bearing, a partition in the sleeve, a spring confined between the head of the screw and the partition to resist endwise movement of the key on the bearing, a detent on the key lever, and a recess on the sleeve in which the detent is normally seated by the spring.

8. In a tabulating mechanism, the combination with a key lever, of a reversible key rotatably and slidably mounted thereon and including a cross-arm having character disks secured to the opposite ends thereof, and a spring operated detent mechanism to prevent accidental turning of the key.

9. The combination with a key lever, of a reversible member rotatably mounted on a bearing on the key lever, and comprising opposite keys, a yielding connection between the member and key lever to permit the member to slide on the bearing, and a detent with which the member is normally held in engagement by its yielding connection to prevent accidental rotation of the keys.

10. The combination with a key lever, of a reversible key rotatably and slidably mounted on a bearing on the key lever, a detent with which recesses in the key are registrable, and a yielding connection between the key and key lever to normally maintain the recesses in engagement with the detent to prevent accidental rotation of the key.

JOHN G. MoLAUGrHLIN.

Witnesses:

K. FRANKFORT, C. RIPLEY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

